How about making your "allies" neutral so it is possible for your characters to kill their citizens or not kill their citizens, and if you do kill somebody, as long as other people see it, then everyone in that village will turn against you and either imprison you for a while or simply terminate your existance.
This makes it more realistic so you can actually hurt anybody you want, and if you attack somebody helpful, then they will refuse to give you advise or the help they would have previously given you.
(They wont attack back if they are ally to you, but you neutral to them, so its impossible for them to attack, and if you do attack them, then they neutral to you so they defend themselves. Or something like that.)
Also
-stealing food, goods, gold etc from dead bodies (inc. animals)
-If you kill a guy with a shield, you can steal his shield, or sword. You dont see it, you simply heighten the attack/hp/armour, which you can do by activating techs etc.
Come back strong like the powered-up pacman.